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Changeset 4539 for branches


Ignore:
Timestamp:
2016-06-18T17:14:19-07:00 (8 years ago)
Author:
Marek Rychlik
Message:

* empty log message *

File:
1 edited

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Added
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  • branches/f4grobner/slow-add.lisp

    r4538 r4539  
    3535        (t
    3636         (rotatef (cdr q) r q))))))
    37 
    38 (defun s-add (p q order-fn add-fn &aux result)
    39   "Non-recursive version of SLOW-ADD. This version uses auxillary variable
    40 RESULT which serves as a stack for the terms of the sum of P and Q."
    41   (loop
    42      (cond
    43        ((endp p) (return-from s-add (nreconc result q)))
    44        ((endp q) (return-from s-add (nreconc result p)))
    45        (t
    46         (multiple-value-bind
    47               (greater-p equal-p)
    48             (funcall order-fn (car p) (car q))
    49           (cond
    50             (greater-p                  ; (> (car p) (car q))
    51              (push (pop p) result)
    52              )
    53             (equal-p                    ; (= (car p)) (car q))
    54              (let ((s (funcall add-fn (lc p) (lc q))))
    55                (cond
    56                  ((universal-zerop s)
    57                   (pop p))
    58                  (t
    59                   ;; Adjust the lc of p
    60                   (setf (lc p) s)
    61                   (push (pop p) result)
    62                   )
    63                  ))
    64              (pop q)
    65              )
    66             (t      ;(< (car p) (car q))                       
    67              (push (pop q) result)
    68              )
    69             ))))))
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